2023? I believe Bruno Putzey/Hypex came up with UCD in the late 90s-early 2000s. I have yet to see a shred of evidence that anyone can distinguish a UCD based Class D amp from any other by using their ears only. I'd certainly be interested in seeing such evidence if someone provides.
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Purifi Amps - Top Choice or No?
- Thread starter ethanhallbeyer
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Np, I actually measured the distortion in the steel tabs well before Amir did...
The amp got to Amir because my test equipment is not as sensitive AND I thought it was just my equipment (and not the amplifier).
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Have not used UcD myself but Amir tested the NAD implementation and it was much noisier. May matter for more sensitive or active speakers but likely moot point as it is very mature…
I recently asked my Hypex rep about having Amir test UcD and he said NCore was better at comparable cost. Ime, this means it is nearing the end of its lifecycle. Even more so when the NC400 is being discontinued and it is much newer.
So he did a blind listening test? Link?
Edit: This? https://www.audiosciencereview.com/forum/index.php?threads/nad-c268-power-amplifier-review.14287/
I would love to see someone here identify it in a blind listening test, without using a 105db horn, ears stuck inside. How about with a 90db, 4-8ohm speaker
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All you will gain here as an answer are individual personal opinions, sometimes coloured by individual interests (OEM manufacturers, equipment sellers).
Any technical engineering design is a balance of compromises, and nothing is ideal. Ideal solution does not exist, we may only approach it emphasizing some features and overlooking other ones.
As a proof that nothing is an ideal solution:
NC252MP (class D) vs. A250W4R (classAB) burst measurements into 4ohm//2.2uF load
NC252MP (class D) vs. A250W4R (classAB) burst measurements into 4ohm//2.2uF load As I have been doing, quite intensively, wide range of power amplifier measurements, I have decided to compare 2 different power amplifier design philosophies, class AB and class D. The amplifiers chosen have equal...
Yes, the bolded part applies very well to you too.
Still waiting for you to post a comment acknowledging that @amirm 's recent PowerCube testing of amps has shown no significant differences with the complex load presented by that device.
I tend to agree. But it's still cool in a geeky way how linear the new stuff is.
Here is a quote from the inventor…
“Ncore merely followed when I started applying this as a tool to optimize a UcD style circuit and increase loop gain whilst keeping the thing stable. The improvement in sound quality was impressive.”
Bruno Putzeys, Sound and Vision May 2017
Bruno is a good engineer, but I doubt his ears are that much better than the rest of us
Still, I couldn't blame him if his new amp sounded best to him.
Still, I couldn't blame him if his new amp sounded best to him.
As I said Rick, any link to a blind/controlled listening tests (same as you would with Toole et al) with specifics, etc....
Harman had big budgets to do blind testing. If you find recent blind testing of power amplifiers, please share the link(s).
As we both indicated that there are likely (at least) fringe cases of audible differences, for anything more, am good with trusting Bruno. If you are not, can take it up with him.
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Big budgets required for loudspeakers, not amps.
Ok, that's no evidence to support say Purifi sounding better than X, much less UcD. Thanks, we agree.If you find recent blind testing of power amplifiers, please share the link(s).
As we both indicated that there are likely (at least) fringe cases of audible differences, for anything more, am good with trusting Bruno. If you are not, can take it up with him.
Of course the OP can buy whatever he pleases, but amp "sound" should be a non starter, unless something is broken or he has some crazy speaker load (not impossible). Personally speaking, I see no need to exempt amp "sound" claims from basic science, aka controlled listening testing. YMMV.
Was he expected to say anything else, like they sound same?
Any results of DBT? I do not think so.After I have made intensive testing of both UcD180 and NC252MP I agree that NC252MP has much better "traditional" parameters like THD measured within 20kHz BW into purely resistive load. Does it matter? I do not think so. Through any known speaker, the resulting THD, IMD and whatever you name of nonlinear distortion it will be finally defined only and only by the speaker. The speaker will mask all the differences between UcD and Ncore measured with a resistor load. UcD has slightly higher noise, but not much. Still very low.
OH sorry, haven't read your comments. Power cube is good to test maximum power into the R + jwL or R + 1/jwC load at 1kHz 1% distortion. Tells nothing about distortion profile below 1%. And we know that the complex load matters re distortion.
And that's probably the key to worse stability of Ncore into capacitive load. See my thread.
Frankly - after my much more intensive testing of the Ncore than that which is done in ASR reviews, I would leave my final opinion on Purifi to the moment I have it on my workbench.
Was he expected to say anything else, like they sound same?
After I have made intensive testing of both UcD180 and NC252MP I agree that NC252MP has much better "traditional" parameters like THD measured within 20kHz BW into purely resistive load. Does it matter? I do not think so. Through any known speaker, the resulting THD, IMD and whatever you name of nonlinear distortion it will be finally defined only and only by the speaker. The speaker will mask all the differences between UcD and Ncore measured with a resistor load. UcD has slightly higher noise, but not much. Still very low.
There never was much question in my mind that most amplifiers will sound the same with passive loudspeakers. As to what Bruno hears, only he can defend.
It is pointless to argue NON-EXISTENT double blind amplifier tests as needed proof in any case. As I stated originally, do not have any UCD modules. If you hook a good dome (high sensitivity) tweeter to your UCD and hear no hiss, then perhaps the noise difference (I have heard in other cases) may not matter. Please also prove your hearing is good enough to hear amp hiss.
Take this one up with Bruno. His quote not mine.
As I have stated many times on this forum, am not an electrical engineer (though I have had engineer in my title more than a few times)!
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Hi
I'm looking at 1ET400A vs Eigentakt EVAL1. With default baseline components.
They're about the same price but I'm not sure which to pick. What are the differences, and/or which would you pick? Budget is ~$1k
I'm looking at 1ET400A vs Eigentakt EVAL1. With default baseline components.
They're about the same price but I'm not sure which to pick. What are the differences, and/or which would you pick? Budget is ~$1k
They will sound completely different
Just kidding. If you can hear a difference, your ears are the best in the world.
They back their products to the hilt for all time to come and have been in business longer than KEF, so while not on the bleeding edge, they are still very much a high end provider. And there is that iconic faceplate.
You're saying they sound the same? That's a valid answer.They will sound completely different
Just kidding. If you can hear a difference, your ears are the best in the world.
Do you know how they compare to this one? https://vtvamplifier.com/product/vtv-amplifier-ncx500-hypex-ncore-stereo-with-input-buffer-options/
Once again, a staright wire with gain. It's cool that the modern amps have such good SINAD, but in reality they are all far better than human ears need.
Comparable in noise and distortion, but NCx500 has a lot more power if you have floorstanding speakers and listen to bass heavy music etc.
BTW in the US Buckeye amps has better inner build than VTV.
Buckeye Amps
Buckeye Amps utilizes the most advanced audio amplifier technologies available. Authorized seller for Hypex and Purifi Class D amplifiers. Based in the US. Free shipping and worldwide service!
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